Electric motor



(No Model.) 2 Sheets-Sheet l.

L. W. STOGKWELL.

ELECTRIC MOTOR.

- No. 291,686. Patented Jen. 8, 1884.

2 Sheets-Sheet 2.

L. L E W K C 0 T S W L. w d o M o m ELECTRIC MOTOR.

Patented Jan. 8, 1884.

frilllu S LL S S E N n W @awww/Mw acitizen ofthe "United States, residing in the I vide an improved switch or device for ruiming Levi n.

ELECTRlC WIG-FOR.

SPECIFICATION forming part of Letters Patent No. 291,626,

dated January 8, 1&4,

Application tiled September F10, 1533. (No modela city of Cleveland, county ot' Cuyahoga, and State of Ohio, have invented certain new and useful Improvements in Electric Motors, ot' which the following is a specification. ,f

The object of my invention is to produce an electric motor in which a maximum effect may be obtained from a given electro-inotive torce, and in which the rotation of the armatureshaft will be caused by continuous action of the tieldinagnet on the armatures, and not by unconnected periodic impulses of attraction or repulsion.

A further object of my invention is to prothe motor in either direction, and for stopping it by rendering the armature neutral, so that the held-magnet acts as a brake to arrest its motion.

Iivhile these are he leading features of my invention, there are other details ot' novelty l fully set forth hereinafter.

In the accompanying drawings, Figure l is,y a transverse section on the line l l ot' Fig. 2. Fig. 2 is a longitudinal section on the line 2 2 of Fig. l. Fig. 3 is an elevation ot` the front end ot" the niotor, showing the controllingswiteh, with the parts partly broken away. Fig. l is a transverse section through a portion ot the motor on the line .JC ot' Fig. showing more especially the arrangement of the controlling-switch and conunutator. Fig. 5 is a diagram view, illustrating the circuits and winding ot' the i'ieldhiagnet and armature l coils.

The field-magnet A A is supported by the end pieces, b, ot' the casing or jacket I3. Itis shown as circular in cross-section, and having its poles c projecting inwardly. rlhe magnet is supported by the elongated ends c, which abut against the end pieces, b, ofthe casing, and are sustained by suitable bolts or screws, and also by bars ot' non-magnetic material, bolted to the field-inag1iet opposite its poles, and i sustained by the end pieces ot the casing. rElie poles a ot' the eldmagnet preferably extend beyond their coils C on cach side, and projectI inwardly somewhat. They are also enlarged l transversely, and present the arc of a circle in cross-section. rEhe coil C is wound continuously around the cores ot the field-magnet in the ordinary way, and one end is connected with a binding-post, D, on the rear end piece ofthe inotor, to which the wire from the positive pole ot' the battery or source ot electric energy is connected, and the opposite end ot' the coil is connected with a binding-p ost, E, on the opposite end piece ot the motor. The

, wire from the negative pole et the battery is connected with a binding-post, I?, also on the front end piece of the machine. rThe binding posts are of course all properly insulated from the casing ot' the motor. rEhe -front end piece Z) is formed with projecting hub, b', which constitutes one bearing ot` the motorspindle S, and also serves as a bearing for the pivoted rocking switch-plate G, which carries on its opposite ends contact-buttons II on the ends oi' insulated bolts or pests I, which project through curved slots in the end piece, b,

`r and carry the coninintator-bruslies, as is hereinafter described. rl`he insulated binding-posts E and E support seniicircular contaetplates Ii L. (Illustrated in Fig. 3, in which iigure the full outlines ot'the plates are indicated by dotted lines.) The ends ot' the contact-plates Ii L are in such close proximity that when the switch-lever 1' turned so as to bring the coni tact-buttons II l etweenthe ends ot' the contactplates these plates bear upon the buttons at both ends. In this position the circuit through l the coils oi` the ticldniagnet will be as follows: Starting t'roin the positive binding-post D, the

circuit runs through the ccilsoi' the held-inagnet to the binding-post Il, contact-plate Ii, contact-batteristi, and opposite plate, L, tothe binding-post In and negative pole ol" the battery. In this position the circuit will of course be shunted 'troni the commutatorbrushes. rIhere will be no current through the armature-coils, and the nieto-r will be atI rest.

I will now proceed to describe the construction and connections oi" the armature magnets and coils. I remark here, however, that the special construction and arrangement of field magnet or magnets and devices already described, may et' coni se be varied, so tar as the other eatures ot' my invention, which remain to be described, are conce ned; and ol course the face of the commutator-ring. Two armathe same principles of construction illustrated l may be also applied to different forms of machines, either of circular or rectangular construction, Without in any ivay departing from the principles of the organization.

The armaturespindle S, which rotates Within the circle ofthe radial teldmagnet poles, has its bearings in the end pieces of the casing, and carries near one end, just inside the end piece, b, a hub of vulcanite or other suitable insulator, M, upon which the coinmutator-plates m fm and a u. are arranged. A collar or flange, N, of some insulating substance, is also carried by this hub on the end adjacent to the armature-coils. The commutator-brushes or contact-fingers o op p, carried by the insulated 'posts I, which project through the end piece, b, and carry the contact-buttons H, bear upon ture-magncts, Q R, with their cores arranged at right angles to the armature-spindle and to each other, and With their greatest transverse width parallel with the spindle and with the length of the cores of the field-magnets, are carried on the spindle S. The poles of these armatureanagnets are enlarged, so as to present the arc of a circle in transverse section, and revolve in close proximity to the correspondingly-curved poles of the iield-magnet. The armature-1nagnet Q is wound continuously in the ordinary way, and t-he terminals of the Wire are connected with the opposite commutatorcontacts a n, While the terminals of the coil of thc magnet R are connected with the opposite commutatorcontacts m m. These connections may readily be traced in the draxvings.

By turning the switchslever G, which earries the posts I, the relation of the commutatOr-brushes 0 p to the colnmutatonplates may be changed, so as to reverse the relative contacts illustrated inthe drawings, and at the same time the contact of the buttons H and the platesKLisreversed. Byswingingtheswitchplate G, therefore, the polarity otthe armaturelnagnets Q R may be reversed at pleasure, and the direction of the motor changed or, by turning the plate to a central position, so that the buttons H come in contact with both of the plates K L, the current will be shunted from the armature-coils, but will still pass through the coils of the held-magnet, which, acting upon the neutral armature-poles, at once bring the armature to rest.

Referring now particulaclyto Fig. l, it will be perceived that the cmmutator brushes, or fingers o are straight, While the iingers p are bent near their ends, so as to cross the straight end ofthe iinger o and give two points of contact to each pair of brushes. he purpose this arrangement is this: lVhen the poles of one of the armature-magnets-say Q-is immediately opposite the poles of the l field-magnet, as illustrated in Figs. l and 2,

the coils of the armature-magnet Q Will be entirely out of circuit, as there is no contact of the brushes o p with the contact-plates a a. l

This magnet, therefore, orl'ers aminimum opposition to the action of the field-magnet on the armature-magnet Vhen, however, the spindle has rotated about twenty-tive degrees, (more orless, so as to bring the poles ot'both armature-magnets into a favorable position to be acted on by the held-magnet, the bent ends of the brushes p make contact With the commutator'plates a, while the brushes o still maintain contact with the plates m. The current is therefore divided and passesthrough the coils of both armature-magnets, so that the poles of the field-magnet act on both otthem, and a maximum effect is obtained. As the poles of the magnet R come opposite the poles of the iield-magnet the brushes o pass from the contact-plates m onto the plates a, so that the coil of the magnet R is cut out of the circuit, and the full current is sent through the coil of the magnet Q. rIhis operation continues as the armature-spindle is rotated, and it will be perceived that the held-magnet acts continuously upon the armature magnets, either upon one magnet only, through the coil of which the whole battery-current is passing when the poles ofthe other magnet are`direct-ly in line with the poles of the lield-mag` net, or upon both armature-magnets when they have passed from the poles of the iieldmagnet.

rlhe details of construction last described may of course be varied without changing the principle of operation herein set forth. For instance, but one commutator-brush having a curved end could be employed in place of each pair of brushes p 0,- but such an arrange ment would not be so good, as it would be difficult to insure contact at the desired points, whereas by employing a pair of crossed brushes perfect contacts at the desired points are insured.

The coils of the armature, it will be seen, are Wound so that their greatestlength is parallel With the armature-spindle, and with the poles of the field-magnet. The poles ofthe field-magnct are equal in length to the combined length of the poles ofthe armature magnets. By arranging the coils of the armature-magnets as described, a maximum et'- fectis produced 5 and this construction, in connection with the method of working' by successively sending the current through both, and then through one only of the coils, a-ccording to the positions they occupy relatively to the field-magnet poles,gives most satisfactory and improved results.

Of course, instead of employing a field-magnet of such a Width as to give a pole equal in length to the combined lengths ot' the armature-magnets, two field-magnets in line with each other might be employed in place of each elongated magnet illustrated; but they should be arranged so that the iield on each side of the armature-spindle will have a uniform polarity, so far as part ot' my invention is conce1-ned. Other parts of the invention are not dependent upon such an arrangement.

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vI construct the commutator by cutting grooves in the face of the hub of vulcanite or insulating material, and letting the commutator-plates into the grooves. The plates are held in place bythe ring N, through which the ends of the armature-coils pass, and are clamped in contact with the plates by screws passing through the ring. I find this construction to be superior to that in which the commutator-ring is formed by attaching` the strips to the face ot' a hub of insulating material, andthen filling' the spaces between the strips, as in the latter construction there is a liability for the parts to loosen and for oil to work in between the plates and the hub.

A pulley, s, either for a cord or band, may be carried upon the end of the spindle to transmit the power ofthe motor, as may be desired.

A full-sized motor, especially designed for ruiming sewing-machines and such like machinery, is shown in the drawings. The same principles of construction and operation may of course be carried out on a larger scale for heavier work. The motor may be attached to any frame by means of a screw-bolt, of nonniagnetic material, and thumb-screw, as illustrated in the drawings.

The action of the field-magnet upon the armature-magnets is continuous, as described, so that the motion is more steady and a greater power is developed than has heretofore been the case in motors of the class illustrated.

It will be observed that the extended pieces c', which support the magnets, are at the neutral parts ofthe field-magnet. I consider this a superior construction to that in which the magnet is supported by cxtensionvpieces run ning from the poles, as in the latter case the magnet is more diffused and is less powerful at the effective point in the motor. The pieces c may be entirely sufficient to support the iieldmagnet, but I prefer for greater strength io also employ the non-magnetic bars ci, extending froni the poles. For the same reason I prefer to make the bolt T, by means ot1 which the special motor illustrated may be secured to its frame, also einen-magnetic materia-l.

This application describes and claims certain subjects-matter described in applications filed by me December 19, 1882, and Hay 19. 1883, and respectively numbered 79,705 and 94,470. IThe present case, however, supersedes and cancels the said earlier applications, so far as any subjectsniatter common to the sev eral applications are concerned, and such subjects-matter have been distinctly disclaimed in the earlier applications.

I claim as my inventionl. The combination, substantially as set forth, of the opposite adjacent iieldunagnet poles, the armatureniagnets arranged transversely to each other and rotating between said poles, the field on each side of the armature being of uniform polarity, the armatureeoils wound parallel with the poles of the fieldmagnet and with their axis ot' rotation and at right angles to their plane of rotation, the

commutator-contacts with which the armature-coils are connected, and the brushes bearing on said contacts and connected with the source ot' electric energy.

2. The combination, substantially as set forth, ot' the opposite adjacent poles of the field-magnet, the armattire-magnetsarranged transversely to ea ch other and rotating between the opposite effective faces of said poles, the

`polarity ofthe iield on each side ofthe armatures being' uniform, the commutator-contacts with which the armature-coils are connected, the brushes bearing on said contacts, and an electric circuit common to said bruslns.

fl. The combination, substantial'y as set forth, ot' the field-magnet having elongated radially-proiecting poles, the arinature-magnets which rotate centrally between the poles and are arranged transversely to each other and have their coils wound with thcgreatest length parallel with the elongated poles ofthe field? magnet, the commutator contacts, and the brushes bearing tl ereon and arranged to send the current successively first through one of the armature-coils, then through both ot' the coils, and then through the other armaturecoil, according to their positions relatively to the field-magnets, as described.

A 4. rlhe combination, substantially as set forth, ofthe field-magnet, the armature-coils, a single commutator-ring, the commutatorcontacts with which the coils are connected, andthe cominutatoirbrushes arrangt d in pairs, one pairon each side ofthe commutator-ring, to give an extended or double point ot' contact on each side ot' the commutator-ring to make connection with one contact before connection with the adjacent one is broken.

The combination, substantially' as set forth, of the tieldmagnct, the armature-coils, the commutator-ring, and the conimutaton brushes arranged to malte contact first with the contact-plates with which one armaturecoil only is connected, and then with both sets ot' contact plates, for the purpose de scribed.

G. The combination, si'ibstantially as set forth, of the field-magnet poles, the transversely-arranged armature-magnets, and electrical connections and contacsby which each armature-maguet is cnt out et' the circuit during a portion of a revolution.

7 The combination, substantially as set forth,ot'thefield-magnet.thearmatnre,thecommutator ring and brushcs,the switch or controlling` device, and the contact buttons and plates by which,\\'hen the switch is in one positiomthe current is shunted from the armature-coils,and when moved in one direction from tl e neutral line sends the current through the armature-coils in one direction, and when put over to the opposite side sends the current in the reverse direction.

S. The combination, substantially as set forth, of the field-magnet, the armature-coils, the coinmutatonring, a switch-lever pivoted concentrieally with the coinmutator-ring, the

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brushes carried by said lever, the contacts through which the battery is shunted from the armaturecoils but still iiows through the held-magnet coils, and the contacts by which the direction of the current through the armature eoils may be reversed by moving` the switch-lever to change the direction ofthe motor.

9. The combination, substantially as set forth, of the field-magnet, the armature7 the commutator-ring,the s\\'it.ch-lever,the brushes carried thereby, and electrical contacts through which by the movement ot' the lever the commntator-brushes are adjusted on the ring and the direction of the current through the armature-coil simultaneously reversed.

10. The combination7 substantially as set forth, ofthe casing or magnet-supports, the tield-magnet, and the supporting-extensions of the magnets projecting` from the neutral part.

LEVI W. "srocKWnLn lVitnesses:

D. DAVIDSON, E. C. DAVIDSON. 

